Tube cleaner



Aug. 29, 1939. g GR|FF|N 2,170,997

- TUBE CLEANER Filed May 23, 1936 NTOR I I MW M Patented Aug. 29, 1939 UNITED STATES PATENT OFFICE TUBE CLEANER Cecil M. Griffin, Pittsburgh, Pa. Application May 23, 1936, Serial No. 81,430 4 Claims. (01. 15-104mm This invention relates to tube cleaning devices, and more particularly to a tube cleaner of the type adapted for use in the cleaning of steam condensing tubes wherein the cleaning tool is propelled through the tube to be cleaned by fluid under pressure. The invention constitutes an improvement over cleaners of the general type shown in my prior patent, No. 1,814,752, dated July 14, 1931.

Tube cleaners of the type to which the present invention relates generally comprise a body having a number of resilient scraper elements supported thereon, these scraper elements being in-' clined to the transverse axis of the body. The lli' scrapers which are slightly resilient engage the inner wall of the tube and remove sediment and encrusted matter. If there is solid matter too firmly encrusted upon the inner wall of the tube or if the tube has some'irregularity, the scraper 2' can yield to clear'such obstruction.

While a tube cleaner as shown in my prior patent has proven highly satisfactory, my present'invention provides a cleaning tool having both right and left hand inclined scrapers. The oppog site inclination of the scrapers prevents rotation of the cleaner in the tube. Moreover, the invention contemplates an arrangement wherein scrapers are distributed along the body of the tool, whereas in my former patent they encircle 30. the body at one place. This arrangement keeps the tool in better alinement and also provides better clearance against clogging. The invention further contemplates'a construction wherein two scraper blades are attached togetheras an in- 5-. tegral unit so that one supports the other, obviating the necessity of a rigid connection of the scraper to the body, or to some auxiliary support on the body, thus simplifying the construction and enhancing the ruggedness of the cleaner. o The present invention, therefore, provides a cleaner which is highly efilcient, can be cheaply manufactured, and is sufficiently rugged to withstand the hard usage to which devices of this type are subjected, particularly when being pro- 45-pelled from the end of a tube at relatively high velocity against a metal plate or back wall. The present invention, moreover, provides a tube cleaner having scraper units of unique construction, the arrangement being such that the clean- 50.er can be easily assembled.

This invention may be readily understood by reference to the accompanying drawing, in which Figure 1 shows a side elevation of a tube cleaner constructed in accordance with the present in- 55 vention;

Figure 2 is an end elevation looking at the rear end of the cleaner shown in Figure 1, part of the end disk being broken away;

Figure 3 is a transverse section in the plane of line III-III of Figure 1; 5

'Figure 4 is an end View of one of the scraper units; 1

Figure 515 an exploded view showing the elements in the order in which they are assembled to form the complete structure illustrated in Fig- 10 ure 1; and

Figure 6 is a perspective view showing one of the scraper uni-ts.

Referring more particularly to the drawing, 2 designates a central stem member .or core. It is 15 preferably square or non-circular in cross section and has an intermediate twist of about 45 between its ends,-asindicated at 2*. A circular head memberd is fittedon-tothe portion 3, and the portion 3 is riveted over as indicated in Figure-land- FigureZ to firmly secure the head member and the stem-memb er. Positioned on thestem member is a plurality of scraper elements 5, 6-, 1 and 8. All of the scraper elements are .of identical construction. One of these elements is shown in detail in Figures 4 and 6. Each of the scraper elements comprises a U-shaped body 9- formed of flat spring metal, the U-shaped body having two leg portions 9 and 9 The connecting part of the body is designated 9 and this connecting part is provided with a square or other non-cir'cularcentral hole Ill. The metal surrounding thehole is pressed or bulged outwardly from the normal plane of the metal, as indicated at Hie. This bulge serves an important purpose reinforcing the scraper and preventing it from bending on a line drawn across it through the hole. Without such bulge the scraper would be weakened across its middle. The free ends of the arms 9 and 9 of the U- 40 shaped body are bent inwardly as indicated at l l and then flare transversely outwardly, providing scraper portions l2. -The outer edges of the scraper portions l2 are curved, these edge portions being designated IS. The curvature of this edge of the scraper corresponds to the curvature of the inside of the tube in which the cleaner is adapted to be used. 'The arm portions 9 and 9 of the U-sh'a'ped body are of reduced width from the central hole l0 toward the inwardly bent portion II, this portion of minimum width being designated M.

The twoblade'portions l2 of the scraper elementsare b oth inclined in the same direction fromia planetransverse to the arms of the U- shaped body. By reason of this, one of the scrapers has a left hand pitch or slope with reference to an axis running through the center of the hole Ill while the other has a right hand pitch or slope.

In the tube cleaner assembly, scraper element 8 is placed on the stem 2 against the head 2*, the stem passing through the central hole l thereof. Following this scraper element, short spacer element i8 is placed on the stem 2, and this is followed by scraper element 1 which is followed by a long spacer l l which is about double the length of spacer l8 and in turn by a scraper element 6, short spacer IS, the last scraper element 5, and finally the second long spacer l5. Afterthe spacer i is in place the head piece 4 is placed on the stem and the end of the stem is then upset or riveted, the countersunk portion'of the head 3 being provided for this upsetting of the end of the stem.

In the assembly, it will be noted that the two scraper units 5 and 6 are at right angles to each other as are also the two scraper elements or units 7 and 8. The scraper combination 56 is turned 45 out of phase-with the combination l-8 by reason of the twist atv 2 in the stem. The non-circular stem 2 engaging in the noncircular openings I0 holds the scrapers from relative rotation. It will be seen that scraper unit 6 overlaps scraper unit 5 and scraper unit 8 overlaps scraper unit I, and that in this overlapping arrangement the base portion 9 of the scraper elements or units 5 and I is between the two arms 9 and 9 of the succeeding scraper element. The arms 9 and 9' of the elements 6 and 8 are clear of the base portion 9 of the elements 5 and I so that all the scraper elements can spring or yield radially inwardly when pressure is applied to the edges of the blades.

The cleaner assembly is inserted in the tube to be cleaned with the end having the disk 4 aftermost. As it is pushed into the tube, the inner wall of the tube will be engaged by the edges 13 of the blades l2. The blades will be pressed or forced inwardly, but the resilience of the metal of which the scraper elements are made springs them out against the inner walls of the tube with sufiicient pressure to provide the necessary cleaning action. At the same time, each blade can move radially inwardly sufiicient to clear such immovable obstructions as are normally encountered in the cleaning operation which these cleaners are adapted to perform.

Each blade l2 extends through an are somewhat greater than 45. By reason of the units 1 and 8 being out of phase with the units 5 and 6, the entire inner wall of the tube will be adequately scraped.

Since all of the scraper elements are the same, the structure or cleaner can be very cheaply manufactured. The structure is easy to assemble, it merely being necessary to assemble the scraper elements on the stem 2 with the spacer elements therebetween and with each scraper element turned 90 to the preceding one. The assembly is such that the arms 9 provide sufficient rigidity to urge the edges l3 of the blades into contact with the inner surface of the tube to be cleaned, but also provide enough spring so that the scrapers can flex inwardly when an immovable obstruction is encountered.

As before stated, by reason of the fact that both blades of each scraper element are inclined in the same direction with reference to a transverse plane through the body, this gives them the efiect, when considered with reference to the longitudinal axis of the body as having an inclination or pitch opposite each other. That is to say, one scraper tends to impart a right hand threading or rotational movement to the body while the other tends to impart a left hand threading or rotational movement. By reason of the metal being cut away at Hi, the blade portions can be bent to shape more effectively and without causing the metal to crimp or buckle, than would be the case if the arms were of uniform width throughout. Moreover, the structure can be more effectively formed by putting the reverse bend ll into the metal just back of the scraper blade. The reverse bend also provides room for the dirt scraped from the tube to get away and thus prevent clogging of the scraper.

While I have specifically illustrated and described one embodiment of my invention, it will be understood that various changes and modifications in the detailed construction thereof may be made.

I claim:

1. A tube cleaner comprising an elongated body member of non-circular cross-section, a plurality of substantially U-shaped scraper elements having non-circular holes therethrough threaded onto said body member, spacers separating the several scraper elements, said body member being provided with means for retaining the scrapers and spacers against longitudinal movement, said scraper elements having blade portions on the free ends thereof, the scraper elements being arranged on the body in such manner that some of the elements overlap other elements, the elements which overlap the other elements being set 90 around from the elements which they overlap, said elements being arranged in groups, said non-circular body member being twisted at an angle of less than 90 intermediate two groups whereby the scraper elements of one group are out of phase with those of another group, the elements being formed. of resilient spring metal.

2. A scraper member for condenser tube cleaners comprising an integral sheet metal stamping of general U-shape form with the outer free end of each arm of the U-shaped piece being turned outwardly perpendicular to the plane of the sheet metal arm of the U-shaped member and at an inclination to a plane which is at right angles to the longitudinal axis of the U- shaped member, such outwardly turned portions forming scrapers, the two scrapers of the member being parallel.

3. A scraper member for condenser tube cleaners comprising an integral sheet metal stamping of general U-shape form with the outer free end of each arm of the U-shaped piece being turned outwardly perpendicular to the plane of the sheet metal arm of the U-shaped member and at an inclination to a plane which is at right angles to the longitudinal axis of the U- shaped member, such outwardly turned portions forming scrapers, the two scrapers of the member being parallel, the metal at the base of the scrapers being bent inwardly in a trough-like form which is wide and deep at one end of the scraper and shallower and narrower at the other end of the scraper.

4. A condenser tube cleaner comprising a central body member having a pair of U-shaped elements non-rotatably carried thereon, one of the elements being longitudinally spaced from the other a distance such that the terminals of the arms of one of the elements come between the terminals and base of the other element, one element being angularly displaced 90 on the body with respect to the other, each of the U- shaped elements being an integral sheet metal structure having a base, arms and terminal por tions at the free ends of the arms, the terminal portions being turned outwardly with respect to the body member to form a scraper, the turnedout portions being set in a common plane which is at an angle to a plane passing at right angles through the longitudinal axis of the U-shaped element.

CECIL M. GRIFFIN. 

